Combined tachometer and revolution-counter.



C. CARSON.

COMBINED TACHOMETER m0 REVOLUTION COUNTER.

APPLICATIONHLEDSEPRZ'I.19H 1,297,793.

Patented Mar. 13, 1919.

INVENTOR A TTOIiWEY UNITED STATES PATENT OFFICE.

CLARENCE CANON, OF NEW ROCHELLE, NEW YORK, ASSIGNOB T0 H. W. JOHNS- KLNVILLE COMPANY, A CORPORATION OF NEW YORK.

column Theseus-rm. am: REVOLUTION-COUNTER.

Specification of Letters Patent.

latented'Mar. IS, 1919.

- Application fled Septcnibcr 24, 1918. Serial No. 255,526.

.cou'ntyof Westchester, State of New York,

have invented certain new and useful Imirorements in Combined Tachometers and 'evolution-Counters, of which the followin is a-specification.

y invention relates to tachomcters and is;-spccifically designed to roduceacompact OOllSil'llCtl0l\ 0f COIIllJlIlQt tachometer and revolution counting mechanism mounted on a unitanfframc and particularly serviceable in recording and indicating-the propeller regblutions of submarines or other marine craftor of a flying machine, or of any revolring body.; The best form of apparatus at. present known to me embodying my invention is illustrated in the accompanying sheet of (hawings in which-1 iE'lis a face view of the apparatus;

Figl. 2 isa. vertical axial section;

"Fig.3 is a detail of the tachometer index shaft operating mechanism, and

Fig. 4 is a detail of the governor links of the tachometer shaft in their relative positions when the apparatus is at rest.

Throughout; this specifi ation like. referenoe characters indiulte like parts. 1. is the cylindrical casing of the hystrmucut,

referably having its back date 2, formed integral with the cylindrica or harrel portion. v3, is the dial plate on which are suitable divisions and figures representing the number of revolutions per minute or other predetermined period. This dial face has a slot 4. or a. series of slots in line. or other form of aperture through which may he seen the nmuerals of the counting mechanism 22. The dial plate also has the. usual central opening 5. through which may profeet the tachonn-tnr pointer shaft J. carry ing the index finger or pointer lo. gl=l plate 7, is held over the dial and index finger Ivy retaining ring 6. and pacing ring or bezel 8.

The tachometer and counting nn-chanisms are mounted upon the main frame ll. which has a lower hearing 12, and an upper hear ing 13. for supporting the main tachonn-tcr shall 14. in a vertical position. This frame ll. has a projecting bos 15. to which the coupling of a flexible tube containing a llcxi ble shaft or other driving means may he.

attached so that rotationmay be imparted to the tachometer shaft 14.

has suitab o, rearwardly projecti lugs 16,

This boss, as. shown 1! Fig. 2,'projects outwardly through an open-m m the casing 1. The frame 11,

16. adapted to bear on the back 5 ate of the casing 1, and when fastened thereto by am pro r mean such as screws, one of whic 1 15 s own at 17, in dotted lines in Fig. '2, hold the frame 11, in proper osition in the casing. 18, 18, are forwart ly projecting lugs similarly adapted to be fastened by screws 19, to the plate 20, of the counting mechanism. This )ltllt 20. is of suitable shape. as nnlicated In Fig. 1. with an opening or lot 21, rc istering with or located behind the slot 4. III the dial face.

22. standard construction mounted on the hack of the plate 20. and so located that the numerals of the counter can be seen through openings 4, and 21. Any. suitable form of helical or other geariughflil. connects the counter mechanism with the main tachomeler shaft 14.

The tachometer mechanism proper con-j nected together b jointed links 26. 26.

which latter are also connected to the centrifugal governor weights 37. 27. spiral compression spring 34. is confined hctwccn collars .34 and normally tending to so )arate the same. The sliding collar 25. \as an external circumferential groove 32. in which ridcsthc anti-friction roller 35. carried hy crank 31, which is carried by shaft ISL journaled in a housing 37 in the rear of plate 20. This shaft 30. carries toothed scetor 29. which meshes with pinion '28. on the lachmncler pointer shaft 9. A light spiral spring! '31. is fastened lo a log on the under :-l(lt' "I" the loollu'd scrim '39. at. Olll' cod and In the plalc J L-althe other end.

The tacln. :wlinks 2 26. have their inner ends which are pivoted together and to the weights 2?. 27. extended beyond the pivotal points aml have outer beveled faces of similar angles of inclination to the axes of the links so that when the. links of each pair swing toward one auother through a certain angle. as indicated in Fig. 2. these howled faces 36. will come to a bearing against the inner fa es of lhe'weighls 27. '37. and prevent further outward movement of is the counter mechanism usualh of position with the I pointer shaft 9, thereb j ustment unaffected 'mechani'sm mounted on a frame said weights, and consequently further action of t e centrifugal governor mechanism.

The method of operation of my invention is as follows: When the parts are at rest the force of gravity acting on wei hts 27 27, and the resiliencyv of spring 32 tend to keep the sliding collar 25, in its lowermost result that the index finger 10, points at zero. The spring 33, also tends to secure the above stated result and takes up lost motion in the connections. When the main tachometer shaft 14, is rotated centrifugal action of the weights 27, causes them to fly outwardly lifting sliding collar 25, turning crank 31, and toothed sector 29, so as to rotate pinion 28, and tachometer y moving the index or pointer 10, to a point opposite the division on the dial face which represents the number of revolutions per minute then being given any shaft to which the governor shaft 18 .pr erly connected as by flexible shaft throng boss 15. When the speed is sufficient to have moved the index fin r around to the limit of the scale the bevei faces 36, 36, on links 26, 26, will come to a bearing on the. weights 27, and prevent further movement of the parts. These beveled faces also have a imiting action on the vertical swinging of t 1 weights 27, 27, on their respective pivots be re the above described stop action comes into efi'ect. contemporaneously with the tachometer action above described the counter mechanism 22, has been operated through gearing 23, to register the total number of rotations of the shaft to which the instrument is connected.

In case cleaning or repair, or the substitution of new parts, is necessary, the retaining ring 6, is removed, the index finger 10, and dial fa'ce taken off, and then by loosening the screws 17, the frame 11, with all the parts carried thereby, may be removed as a unit and the necessary cleaning, inspection or repairs made, after which the a paratus is put'back in the case as a unit. This method of mounting also insures the accurate adjustment of all the parts with reference one to an ther and leaves that adby expansion, contractlon, or warping of the casmg 1, or of the dial face.

Having described my invention, I claim: 1. A combined tachometer and counting adapted to be inserted oi removed as a. unit from a pro er casing having a dial face provided wit a central opening and a horizontally extending opening, which mechanism comprises a frame having opposed bearings, a tachglmeten shaft journaliid therein, frearwar y progectmg spac' ugs on t rame adapted to bear again s t the back plate of the casing, and provided with fas means thereto, and similar forwardly proecting lugs on said frame, a plate mounted on said last mentioned lugs andprovided with an aperture ada ted to register with the above mentioned dial face openings and with a perforation adapted to register with the central opening in the dial, a counting mechanism mounted on this plate behind said horizontally extending opening, a tachometer inter shaft journaled in and projecting t rough the perforationin said plate, a centrifugal governor mechanism mounted on the tee ometer shaft and geared to the pointer shaft, and gearing connecting the counting mec nism and the said tachometer shaft.

2. The tachometer I anism described in claim 1 combined with a cylindrical casing having a back provided with perforations registering with the rearwardly extending lugs on the main frame, a dial face having an opening, with the aperture in the counter supporting plate, a glass cover for the casing, spacing means between the dial and glass cover, and a retaining ring for holding these arts assembled, together with an index and mounted on the tachometer pointer shaft and iocated between the dial and the glass cover plate.

3. A centrifugal governor mechanism comprising in combination a rotatable shaft, a plurality of weights, a sliding sleeve on the shaft, and pairs of links pivoted to the shaft and sleeve at their outer extremities and to one another and to the weights at inner extremities, the inner overlapping ends of the links having beveled outer faces adapted and counting mechto bear against the weightswhen the weights apre+ 

